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Population structure of Araucaria angustifolia under distinct forest protection status:implications for management and conservation

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林业研究:英文版 2023年第5期34卷 1437-1446页

作者： Vinicius costa Cysneiros Allan Libanio Pelissari Sylvio Pellico Netto Sebastiao do Amaral Machado Afonso Figueiredo Filho Departamento de Agricultura Biodiversidade e FlorestasUniversidade Federal de Santa Catarina-UFSCRodovia Ulysses GaboardiKm 03CuritibanosSC 89520-000Brazil Departamento de Ciencias Florestais Universidade Federal do Paraná-UFPRAv.Prof.Lothario Meissner632CuritibaPR 80210-170Brazil Departamento de Engenharia Florestal Universidade Estadual do Centro-Oeste-UNICENTROPR-153Km 7IratiPR 84500-000Brazil

Araucaria angustifolia is the dominant coniferous species in Brazil,a long-lived pioneer species and a supplier of valuable timber and non-timber products,which gives it key-species *** study examines how *** population structure affects the stand structure,and whether these relationships differ between protected and unprotected *** study was carried out on two protection status forests(national forest and urban forest)in a region of Atlantic mixed forest in ParanáState,southern *** coefficient and the Weibull shape parameter described the population structure and its effects on species diversity and biomass *** diameter distribution differed significantly between forests,with unbalanced structure in both,although regeneration was more abundant in the protected *** positively affected aboveground biomass whereas shape negatively affected it and species *** relationships differed between protected and unprotected *** effect of *** populations on stand structure was conditioned on protection ***-growth populations may have lower diversity and biomass stock even supporting large ***,old-growth forests,can lead to wood loss through mortality,senescence,and declining populations,representing the waste of a valuable timber *** findings provide useful knowledge for forest management,species conservation,and the carbon market.

关键词： Key species Diameter distribution Weibull shape parameter Aboveground biomass

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Research on Activation Method of Recycled Brick Powder

Research on Activation Method of Recycled Brick Powder

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作者： Nidia Alves da.costa 北京交通大学

学位级别：硕士

在过去的十年中,随着环境挑战的提出,固体废弃物的再生利用成为一个极具环保效益与经济效益的研究热点。近年来,人们对利用建筑垃圾与工业废物协同制备辅助胶凝材料(SCM)进行了大量的研究,以帮助减少建筑垃圾对环境的影响。最近的研究表... 详细信息

在过去的十年中,随着环境挑战的提出,固体废弃物的再生利用成为一个极具环保效益与经济效益的研究热点。近年来,人们对利用建筑垃圾与工业废物协同制备辅助胶凝材料(SCM)进行了大量的研究,以帮助减少建筑垃圾对环境的影响。最近的研究表明,建筑垃圾的再生产品——再生微粉具有一定的活性,可尝试制备胶凝材料,但相关学者发现,无论再生粉的粒度和来源如何,再生微粉掺入到普通硅酸盐水泥中的最佳掺量限制在0-30%。水泥掺量大于30%的混合料的抗压强度和抗折强度明显降低。为了提高再生粉替代传统水泥的采用,学者们使用活化方法来激发混合料中再生微粉的活性。通过研磨再生微粉的机械活化、使用分级助剂和混合再生微粉的化学活化以及纳米Ca CO3料浆活化是再生微粉最常用的活化方法。因为赤泥中含有强碱矿物,本研究研究了以赤泥为可持续建筑材料替代水泥的再生微粉的活化方法,通过对再生微粉机械活化方法进行不同配合比、不同材料替代率下试件力学特性的室内试验。实验1结果表明,赤泥本身不会活化再生微粉,因此实验2使用水泥含量低激活再生微粉的混合物。这个实验的结果表明,添加水泥混合设计增加了整体抗压强度,在使用30%的水泥和35%至50%再生微粉时胶凝材料获得最佳效果。本实验的第一部分使用赤泥作为再生粉的活化剂,制备砂浆试件。第二部分提出水泥作为赤泥和再生微粉的活化剂,利用水泥水化产生的氢氧化钙Ca(OH)2活化赤泥和再生微粉中的硅、铝矿物。通过7天和28天的抗压和抗折强度试验确定了水泥活化赤泥再生微粉的力学性能,确定了最佳配合比设计。

关键词：再生微粉赤泥活化法建筑垃圾硅酸盐水泥

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Hole-doping induced ferromagnetism in 2D materials

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npj Computational Materials 2022年第1期8卷 2180-2189页

作者： Ruishen Meng Lino da.costa Pereira Jean-Pierre Locquet Valeri Afanas’ev Geoffrey Pourtois Michel Houssa Department of Physics and Astronomy KU LeuvenCelestijnenlaan 200DLeuvenB-3001Belgium imec Kapeldreef 75B-3001LeuvenBelgium

Two-dimensional(2D)ferromagnetic materials are considered as promising candidates for the future generations of spintronic ***,2D materials with intrinsic ferromagnetism are ***,high-throughput first-principles simulations are performed to screen 2D materials that present a non-magnetic to a ferromagnetic transition upon hole doping.A global evolutionary search is subsequently performed to identify alternative possible atomic structures of the eligible candidates,and 122 materials exhibiting a hole-doping induced ferromagnetism are *** energetic and dynamic stability,as well as magnetic properties under hole doping are investigated *** of these 2D materials are metal halides,followed by chalcogenides,oxides,and nitrides,some of them having predicted Curie temperatures above 300 *** exchange interactions responsible for the ferromagnetic order are also *** work not only provides theoretical insights into hole-doped 2D ferromagnetic materials,but also enriches the family of 2D magnetic materials for possible spintronic applications.

关键词： ferromagnetic doping materials

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Prediction of ground-borne vibration induced by impact pile driving:numerical approach and experimental validation

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Earthquake Engineering and Engineering Vibration 2023年第4期22卷 921-935页

作者： A.Colaço P.Alves costa C.Ferreira C.Parente J.Fernandez-Ruiz CONSTRUCT-FEUP University of PortoRua Dr.Roberto Frias4200-465 PortoPortugal University of La Coruña Department of Civil EngineeringCampus de Elviña 15071La CoruñaSpain

Deep foundations are currently used in engineering practice to solve problems caused by weak geotechnical characteristics of the *** pile driving is an interesting and viable solution from economic and technical points of ***,it is necessary to ensure that the environmental drawbacks,namely ground-borne vibration,are adequately *** this purpose,the authors propose an axisymmetric finite element method-perfectly matched layer(FEM-PML)approach,where the nonlinear behavior of the soil is addressed through an equivalent linear *** the complexity of the problem,an experimental test site was developed and fully *** experimental work comprised in-situ and laboratory soil characterization,as well as the measurement of vibrations induced during pile *** comparison between experimental and numerical results demonstrated a very good agreement,from which it can be concluded that the proposed numerical approach is suitable for the prediction of vibrations induced by impact pile *** experimental database is available as supplemental data and may be used by other researchers in the validation of their prediction models.

关键词： pile driving ground-borne vibrations numerical modeling experimental validation

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Compounds from Stevia rebaudiana Bertoni leaves: An overview of non-conventional extraction methods and challenges

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Food Bioscience 2022年第2期46卷 108-121页

作者： Dj´essica Tatiane Raspe Camila da Silva Silvio Cl´audio da.costa ograma de P´os-Graduaç˜ao em Ciˆencia de Alimentos Universidade Estadual de Maring´aAv.Colombo579087020-900Maring´aPRBrazil Departamento de Tecnologia Universidade Estadual de Maring´aAv.ˆAngelo Moreira da Fonseca180087506-370UmuaramaPRBrazil Departamento de Bioquímica Universidade Estadual de Maring´aAv.Colombo579087020-900Maring´aPRBrazil

To overcome the inconveniences related to its conventional obtainment of natural sweeteners and active compounds from Stevia rebaudiana Bertoni,methods involving application of technology,such as ultrasound assisted extraction,microwave assisted extraction,extraction under pressurized conditions by means of pressurized liquid extraction,subcritical water extraction and supercritical fluid extraction have been *** this review,these emerging techniques were analyzed and discussed,the process variables and operational strategies,their impacts on the extraction and their comparison against the conventional techniques were *** and the possibility of operational automation,the use of less energy and solvents,in addition to the reduced complexity of the subsequent purification steps,make up viable alternatives suitable for a possible industrial *** processes leverage the concept of green chemistry,but still suffer limitations related to acquisition and maintenance costs,in addition to the effects of the action of some of these technologies remaining unexplored.

关键词： Active compounds Natural sweeteners Steviol glycosides Technology application

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Delay Times and Clinical Outcomes in Acute Myocardial Infarction: Comparison of Periods before and during the COVID-19 Pandemic—Myocardial Infarction and the Pandemic

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World Journal of Cardiovascular Diseases 2024年第6期14卷 392-400页

作者： Clarice Teixeira Silva Araújo Arnon Salviato Mameri Thúlio Carrera Guarçoni Venturini Marcus Tadeu Aguilar Constantino Matos Igor Morais Araujo Lopes Luiz Gustavo Ribeiro de Carvalho Murad Cleberson Duartes Ovani Guilherme Vassalo Morais Fernanda Venturini de Castro Danielle Lopes Rocha Lucas Crespo de Barros Rodolfo costa Sylvestre Luiz Fernando Machado Barbosa Roberto Ramos Barbosa Internal Medicine Universidade Federal do Esprito Santo (UFES) Vitria Brazil Hospital Santa Casa de Misericrdia de Vitria Vitria Brazil Hospital Santa Rita de Cssia Vitria Brazil Hospital Estadual Dr. Jayme Santos Neves Serra Brazil Grupo Kora Sade Vitria Brazil Hospital Estadual Infantil e Maternidade Alzir Bernardino Alves (HIMABA) Vila Velha Brazil

Introduction: At the beginning of the COVID-19 pandemic, a drop in the number of patients treated for cardiac emergencies raised concern about cardiovascular mortality in that period. An increase in care delay for patients with ST-segment elevation myocardial infarction (STEMI) may have affected clinical outcomes. Objectives: To analyze delay times and clinical outcomes of patients with STEMI undergoing primary percutaneous coronary intervention (PPCI), before and during the COVID-19 pandemic. Methods: Retrospective observational study that included patients with STEMI undergoing PPCI from December 2018 to July 2021. The COVID-19 pandemic cases were divided into two groups: pandemic I—from March to August 2020;and pandemic II—from September 2020 to July 2021. Patients were compared according to the period of hospitalization. Primary outcomes were delay times in assistance and clinical outcomes (acute kidney injury [AKI], post-procedural vascular complications and in-hospital mortality). Results: 108 patients were included, 39 (36.1%) in the pre-pandemic period, 13 (12.1%) in pandemic I and 56 (51.8%) in pandemic II. Time from onset of symptoms to arrival at the service and door-to-balloon time did not differ significantly among groups. Vascular complications were more frequent during the pandemic (I and II) than in the pre-pandemic period (2.5% pre-pandemic vs 15.4% pandemic vs 12.5% pandemic II;p = 0.03). AKI incidence was similar in all three periods. There was a non-significant increase in in-hospital mortality during the COVID-19 pandemic. Conclusion: In patients with STEMI, there was an increase in vascular complications and a trend toward increased mortality during the COVID-19 pandemic. Delay times to admission and reperfusion did not differ significantly between before and during the pandemic.

关键词： Myocardial Infarction Primary Percutaneous Coronary Intervention Coronary Reperfusion Pandemic COVID-19

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Sorption and desorption behavior of residual antidepressants and caffeine in freshwater sediment and sewage sludge

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International Journal of Sediment Research 2022年第3期37卷 346-354页

作者： Ismael Laurindo costa Junior Christiane Schinneider Machado Adelmo Lowe Pletsch Yohandra Reyes Torres Department of Chemistry Federal University of Technology-Paraná (UTFPR) Department of Chemistry State University of Midwest (UNICENTRO)

The use of antidepressants is widespread in modern times. Thus, they present a potential risk for ecosystems due to occurrence in domestic sewage containing unaltered metabolites and structures, even after the treatment plants have processed the sewage. The current research investigated the sorption and desorption of antidepressants(citalopram, venlafaxine, fluoxetine, sertraline, and amitriptyline) and caffeine from freshwater sediment and sewage sludge. The samples of freshwater sediment were collected in a river spring in an area with few anthropogenic sources of pollution and samples of sewage sludge were taken from stabilization ponds of a sewage treatment. The matrices were mainly composed of organic fractions, sediment of humic nature, and aliphatic biomolecules in sludges. The presence of silt and clay in the sediment proved to be important for the sorption process when compared to the flocs and colloidal structure of the sludge. The kinetic study indicated pseudo-first order behavior. The Freundlich isotherm was satisfactorily used in the interpretation of sorption and desorption for all analytes and matrices. The high percentages obtained for desorption suggest analyte mobility, which is more intense in the sludge than in the sediment since each matrix has a different composition. It can be considered that the information obtained here reinforces the ecotoxicological concern with respect to pharmacological residues in the environment, as processes of retention by sorption in the sludge and the sediment have been confirmed, as well as the preferential partition of some analytes by the aqueous phase.

关键词： Emerging pollutants Drugs Persistence Partition Mobility Sorption

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Characteristics of leukemic stem cells in acute leukemia and potential targeted therapies for their specific eradication

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Cancer Drug Resistance 2022年第2期5卷 344-367页

作者： Quinty Hansen costa Bachas Linda Smit Jacqueline Cloos Department of Hematology Amsterdam UMCLocation VUmcCancer Center AmsterdamAmsterdam 1081HVThe Netherlands

In acute myeloid leukemia(AML),a small cell population that contains stem cell features such as lack of differentiation,self-renewal potential,and drug resistance,can be *** so-called leukemic stem cells(LSCs)are thought to be responsible for relapse initiation after initial treatment leading to successful eradication of the bulk AML cell *** many studies have aimed to characterize and eliminate LSCs to prevent relapse and increase survival rates of patients,LSCs are one of the best characterized cancer stem *** specific elimination of LSCs,while sparing the healthy normal hematopoietic stem cells(HSCs),is one of the major challenges in the treatment of *** review focuses on several surface markers and intracellular transcription factors that can distinguish AML LSCs from HSCs and,therefore,specifically eliminate these stem cell-like leukemic ***,previous and ongoing clinical trials of acute leukemia patients treated with therapies targeting these markers are *** contrast to knowledge on LSCs in AML,insight into LSCs in acute lymphoid leukemia(ALL)is *** review therefore also addresses the latest insight into LSCs in ALL.

关键词： Acute myeloid leukemia acute lymphoid leukemia leukemic stem cells targeted therapy

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Asymmetric hydrogenation and transfer hydrogenation in the enantioselective synthesis of flavonoids

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Organic Chemistry Frontiers 2022年第4期9卷 1165-1194页

作者： Guilherme S.Caleffi Felipe C.Demidoff Carmen Najera Paulo R.R.costa Laboratorio de Quimica Bioorganica(LQB) Instituto de Pesquisas de Produtos NaturaisUniversidade Federal do Rio de JaneiroAv.Carlos Chagas Filho 373Bloco HCidade Universitaria21941-902 Rio de Janeiro Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA) Universidad de AlicanteApdo.99E-03080 AlicanteSpain

Asymmetric hydrogenation(AH)and asymmetric transfer hydrogenation(ATH)are versatile synthetic methodologies widely employed in the preparation of chiral *** this review,we explore the applications of AH and ATH in the total synthesis of natural flavonoids and their analogues,highlighting the limitations and opportunities in the field.

关键词： compounds field hydrogenation

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Stable NiO-CeO_(2) nanoparticles with improved carbon resistance for methane dry reforming

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Journal of Rare Earths 2022年第1期40卷 57-62页

作者： Andrea Cárdenas-Arenas Esther Bailón-García Dolores Lozano-Castelló Patrick Da.costa Agustín Bueno-López Department of Inorganic Chemistry University of AlicanteCarretera de San Vicente s/nE03080AlicanteSpain Sorbonne Universite Institut Jean Le Rond d'AlembertCNRS UMR 71902 place de la gare de ceinture78210Saint Cyr L'EcoleFrance

High surface area mixed oxide 8.7%NiO-CeO_(2) nanoparticles(122 m2/g;6-7 nm)were prepared using a reversed microemulsion method,and were tested for dry methane reforming(DRM).The catalytic activity of these nanoparticles remains stable under the severe conditions of DRM(700℃),and they show better carbon resistance than conventional NiO-CeO_(2) catalysts prepared without control of the *** activity and selectivity of nanoparticles and reference catalyst are similar,but nanoparticles reduce the accumulation of carbon by 63%during the DRM tests,which is a key feature for this *** and H_(2)-TPR suggest that the improved carbon resistance of the nanoparticles is due to the better interaction and cooperation between NiO and CeO_(2) mixed *** nanoparticles,the participation of cerium cations in the redox processes taking place during DRM stabilizes cationic species of *** the contrary,the catalyst prepared without control of the size suffers segregation of Ni during DRM reaction,and segregated Ni explains the higher catalytic formation of carbon.

关键词： Methane dry reforming Nickel Ceria Nanoparticle Rare earths

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